There are several strategies that can be used to win in fantasy baseball, but one of the most tried and true is being able to identify breakout players and avoid those who are going to disappoint.
Major League Baseball teams make it difficult to parse out which potential rookies will really have great years because of all the service-time manipulation that takes place. There are certainly young players you can look at and see the star potential, even if they don't start the year in the big leagues.
On the other hand, a bust can be tricky to pinpoint because by its very nature, it implies a player with some sort of track record of success and good performance the previous year.
Rather than get overwhelmed with all of the numbers required to study which players will be breakout performers and busts in 2021, here is a list of sleepers to target in your draft and overrated players to avoid.
Sleeper: Zach Eflin, SP, Philadelphia Phillies
A former first-round pick in 2012, Zach Eflin looks to be trending in the right direction after two solid seasons with the Philadelphia Phillies.
Eflin was a quality starter in 2019 with a career-high 163.1 innings pitched, 4.13 ERA and 1.35 WHIP. Those aren't numbers that are going to light the fantasy world on fire, but they helped him solidify his standing as a legitimate mid-rotation pitcher.
Last year was Eflin's breakout year. He finished with a 3.97 ERA, 70 strikeouts and a 1.27 WHIP in 59 innings. It's tricky to know how much of that is repeatable because of how short the 2020 season was, so let's look at some of the underlying numbers that helped him get to those numbers.
Eflin's average fastball velocity of 93.9 mph was the second-fastest of his career (94.3 mph in 2018). He also threw his curveball more than ever (13.1 percent) and has continued to increase usage of his cutter (5.9 percent).
Per Baseball Savant, opponents hit .100 with a .125 slugging percentage against Eflin's curveball with a whiff rate of 43.9 percent last year.
The fastball has some sink to it that led to him generating a career-high groundball rate of 47.4 percent. He's still more homer-prone than you would like to see (1.22 per nine innings), but the rest of his stats indicate the right-hander is at least capable of being a top-50 starter in 2021.
Eflin is currently the 75th pitcher coming off the board with an average draft position of 195, per Fantasy Pros.
By comparison, Corey Kluber has pitched a total of 36.2 innings the past two years combined and will pitch in the American League East with the New York Yankees. He's going 43 spots ahead of Eflin in fantasy drafts right now.
Bust: Aaron Judge, OF, New York Yankees
In order to actually hit those numbers, though, you have to play. Since playing in 155 games as a rookie in 2017, Judge has played a total of 242 out of a possible 384 games over the past three seasons.
Some of Judge's injury issues have just been bad luck. He missed 46 games in 2018 with a broken bone in his wrist after being hit by a pitch against the Kansas City Royals.
The past two years have seen Judge miss time due to non-contact injuries. He strained his oblique in 2019 and dealt with a stress fracture in his ribs in 2020.
Despite Judge's growing injury report, he's got an average draft position of 49. Certainly, if he stays healthy, a fourth-round pick ends up looking like a bargain. But there's been no evidence recently to suggest the two-time All-Star is going to play at least 120 games in 2021.
Sleeper: Will Smith, RP, Atlanta Braves
The value on closers in fantasy, much like in the real world, often gets overrated because it's a position that no team wants to have instability at.
Just looking at average draft position for closers, there are six currently going in the top 100 picks. From that group, though, there's a great deal of uncertainty. Aroldis Chapman is the safest player in the group because of his track record, but he's lost fastball velocity in each of the past three years. He still averaged 98.1 mph with the heater last season, so it's not like he's easy to square up.
Josh Hader, whose ERA has gone up each year of his career and hit a 3.79 mark last year, is the top reliever coming off the board. Edwin Diaz went from being removed as the New York Mets closer in 2019 to posting a career-best 1.75 ERA in 2020.
In other words, there's no reason to be pressured into taking one of the top closers because there's going to be great depth at the position in the later rounds.
Atlanta Braves reliever Will Smith has great sleeper potential coming off a down year. The left-hander posted a 4.50 ERA and allowed seven homers in just 16 innings, but most of that damage came in the first month of the season.
In 10 appearances during September, Smith had a 3.24 ERA with four hits allowed and 10 strikeouts over 8.1 innings.
Braves manager Brian Snitker has said he's keeping all of his options open for the team's closer role in 2021.
Smith likely has the inside track because of his history of success and by virtue of making $13 million per season on his current contract. If teams are paying that kind of money for a reliever, they typically want them throwing the most high-leverage innings to maximize the value.
In his three seasons prior to 2020, Smith posted a 2.70 ERA with 193 strikeouts in 136.2 innings as a member of the San Francisco Giants. He did miss the 2017 season due to Tommy John surgery but returned with no issues in mid-2018.
Smith is currently the No. 27 reliever being selected with an average draft position of 189 overall. He certainly comes with more volatility than the top group of players at the position, but it's not a position where you go to for stability anyway. It's a crapshoot every year, and the smart move is to bet on a player who will likely be given the ninth-inning role for a good team.
Bust: Any Tampa Bay Rays Starting Pitcher
Coming off an appearance in the World Series, the Tampa Bay Rays decided to get rid of their two most reliable starting pitchers this offseason.
Charlie Morton signed a one-year contract with the Atlanta Braves after the Rays declined his $15 million option. Blake Snell was traded to the San Diego Padres for Francisco Mejia and three prospects.
Since the Rays aren't looking to spend a lot of money on players, Snell and Morton were replaced by Michael Wacha and Chris Archer.
Granted, Morton wasn't a dominant player last season. He posted a 4.74 ERA in 38 innings and had his lowest strikeout rate (9.95 per nine innings) since 2016.
But Wacha and Archer haven't been front-line starters since 2015. Wacha's 6.62 ERA last year was tied for 142nd out of 158 pitchers with at least 30 innings.
Archer's career fell off a cliff after the Rays traded him to the Pittsburgh Pirates in July 2018. The two-time All-Star had a 4.92 ERA with 203 strikeouts in 172 innings with the Pirates. He missed the entire 2020 campaign after undergoing surgery for thoracic outlet syndrome.
In addition to Archer and Wacha, the Rays starting rotation is expected to include Tyler Glasnow, Ryan Yarbrough and Rich Hill.
Glasnow has the highest ceiling in that group and did post a 1.78 ERA two years ago but only pitched 60.2 innings that season. He's only reached the 100-inning barrier once in five MLB seasons.
The Rays don't use starting pitchers like most teams anyway. They have a set plan on how long they want their starter to go, at which point manager Kevin Cash will go the bullpen. That's part of the reason why Snell was pulled from Game 6 of the World Series in the sixth inning, despite allowing just one run from two hits on 73 pitches.
Until the Rays decide that they are going to let their starters go, no one projected to be in their rotation this season is worth rostering.